Method of shrinking



Aug. 4, 1964 F. P. MURPHY ETAL Re. 25,629 METHOD OF SHRINKING, DYEINGAND FINISHING Original Filed June 24. 1960 IN ENTORS 1:21? /z'y UnitedStates Patent Ofi ice Re. 25,629 Reissued Aug. 4, 1964 Original No.3,083,074, dated Mar. 26, 1963, Ser. No. 38,554, June 24, 1960.Application for reissue Apr. 29, 1963, Ser. No. 276,681

2 Claims. (Cl. 8-18) Matter enclosed in heavy brackets [II appears inthe original patent but forms no part of this reissue specification;matter printed in italics indicates the additions made by reissue.

The present invention relates to method of preshrinking, dyeing andfinishing garments made of knitted fabric.

A purpose of the invention is to produce a finished garment from knittedfabric such as cotton Jersey cloth which is stable against furthershrinkage on washing.

A further purpose is to obtain a softer and more relaxed hand or feel onknitted garments.

A further purpose is to produce a garment from knitted fabric which willbe more comfortable to the wearer and free from the scratchy feelingwhich has been produced by such garments in the past.

A further purpose is to produce garments from knitted fabric which havea more relaxed appearance and more uniform stitch distribution.

Further purposes appear in the specification and in the claims.

In the drawings we illustrate mechanism which will be useful inperforming the process of the invention.

FIGURE 1 is a diagrammatic perspective of a conventional paddle dyeingmachine useful in the invention.

FIGURE la is a perspective of the work in a mesh bag.

FIGURE 2 is a diagrammatic front elevation of a suitable cylindricaltumbling mechanism applicable in the invention.

Considerable difficulty has been encountered in the dyeing and finishingof knitted fabrics and especially cotton Jersey cloth of the characterwhich is primarily used for underwear such as undershirts and shorts,and for outer wear such as sport shirts, jackets and other similargarments.

The usual practice has been to dye and finish the cloth in the form ofpiece goods under tension in a jig or a dye beck.

The resulting finished garment has exhibited considerable tendency forfurther shrinkage, leading to distortion and misshaping after one ormore washings.

Also the fabric produced in the prior art has had a rather stiff orharsh feel, and there has been some tendency of the garment or cloth tobe scratchy or otherwise uncomfortable to the wearer.

There has also been a tendency for the stitches to be nonuniform in thefinished garment or cloth due to uneven shrinkage elfects.

In accordance with the present invention an improved preshrinking,dyeing and finishing technique is applied which results in a number ofdifferent advantages.

In the first place the tendency of the finished fabric to furthershrinkage is largely eliminated, so that on subsequent washing thefabric will have a shrinkage in any case not over 1% in eitherdirection. This results in a very relaxed appearance of the fabric withuniform knitted stitches in both directions.

One of the advantages of the present invention is that the garmeiit andthe cloth are more relaxed in hand or feel and softer, and the resultinggarment is more comfortable and less likely to feel scratchy orotherwise uncomfortable to the wearer.

The finished garment of the invention may be washed repeatedly withoutany tendency to get wider or shorter or vice versa, and without anyother tendency to distort in shape.

In accordance with the invention the dyeing and finishing are carriedoutwith the garments or fabrics completely relaxed and contained in meshor other suitable dyeing bags. As distinguished from the prior art,there is no tension whatever applied during dyeing or finishing.

Furthermore, in accordance with the invention, after dyeing andfinishing the garments or fabric are tumbled to dry them and to work thefabric, thus resulting in increased softness and much greater comfort tothe wearer.

Considering now the drawings in detail, the garments 20 of the inventionas shown in FIGURE 1a are first placed in mesh bags 21, each of whichdesirably contains about 20 pounds of knitted fabric or garments(maximum).

A scouring bath is then made up in a conventional paddle dyeing machine22 having power operated paddle 23 as well known, rotated by a suitabledrive on a suitable horizontal axis.

The scouring bath consists of water to which a scouring detergent hasbeen added, capable of removing waxes, impurities, knitting oils andother foreign matter. While conventional cleaning agents such as sodiumand potassium soaps may be used, it is decidedly preferable to use along chain fatty alcohol having a carbon chain length of between 14 and30 carbon atoms, such as lauryl alcohol, myristyl alcohol, cetylalcohol, stearyl alcohol, palmityl alcohol or oleyl alcohol.

The concentration of the detergent should be about 1 to 6 percent on theweight of the goods, preferably about 4 percent, and the ratio of thebath should be about 30 to 1 (times the weight of the goods). Thetemperature of the scouring bath should preferably be between about and190 degrees F.

During scouring the propeller of the machine churns the loose mesh bagscontaining the goods and agitates the goods and circuates the baththrough the fabric.

After scouring is complete the bath is dropped.

After completion of the scouring, a rinse bath of water at a temperaturebetween about 130 and F. is made up having the same volume as thescouring bath and the machine is run to circulate the rinse bath withrespect to the goods in the mesh bags. The function of the rinse bath isparticularly to remove alkali. The rinse bath is then dropped and if therinse bath has been substantially clean it will not be necessary to usea second rinse, but if the rinse bath has not been clean a second rinsebath will be made up and the machine run with the second rinse bath.Usually one rinse bath is sufiicient.

Next a water bath for dye is made up, and a suitable dye is introducedsuch as a direct dye of which the following are examples.

Solontine Yellow RL (Color Index No. Direct Yellow 50) Solontine Blue 2GL (Color Index No. Direct Blue 81) Solontine Orange G (Color Index No.Direct Orange 34) Solontine Blue Green FWL (Color Index No. Direct Green27) Solontine Red 8 BLN (Color Index No. Direct Red 80) Solophenyl Blue3 GL (Prototype No. 443) The concentration of dye will be between about0.10 and 1.0% on the weight of the goods.

The fabric is run in the dye bath, the propeller of the machinecirculates the bath and the bags of fabric relatively to one another sothat fabric takes up the dye uniformly.

After completion of the dyeing, the dye bath is dropped.

Next a rinse bath as previously described is made up having atemperature between 90 and 100 F. and the propeller is. operated tocirculate the fabric in'the bags with respect to the water of the rinsebath and remove excess dye. The first rinse bath is dropped and if itdid not come up fairly clean, rinsing will be repeated until the rinsebath is clean.

Next a water bath to contain finish is made up. This bath has the samevolume as that previously described, and will contain a cationic type offinish, preferably an amide of a fatty acid having a carbon chain lengthbetween l4 and 30, such as stearyl amide, palmityl amide, lauryl amide,myristyl amide or cetyl amide. The concertration of amide of fatty acidwill preferably be in the range between 2 and 3% on the weight of thegoods. The machine is run to thoroughly circulate the finish through thegoods so that the goods will take up the finish, the finish bath isdropped and the goods are removed in the bags and extracted as by acentrifuge to remove the excess of water.

The goods are then removed from the bags, and this step is quiteimportant. The loose fabric or clothing is then tumbled in a tumblingmachine or drum 24 rotating on shafts 25 and having a suitable door 26.The tumbling machine turns about 6 to 10 r.p.m. and suitably has adiameter of about 4 to 10 feet.

The effect of the tumbling is to dry the good and also relax the fibersand relax and equalize the stitch, removing any localized tensions whichmay exist in the fabric so that the fabric comes up more uniform inappearance and is more soft and relaxed in respect to the hand or feel.

The times of the various operations will suitably be as follows:

Scouring 15 minutes to an hour and preferably about 30 minutes.

Rinsing 5' minutes to an hour and preferably about minutes.

Dyeing 1 to 3 hours and preferably about 2 hours.

Finishing minutes to an hour and preferably about 30 minutes.

Extraction 5 to minutes and preferably about 10 minutes.

T umbling 30 minutes to 2 hours and preferably about 1 hour.

The following is a detailed example of a preferred embodiment of theinvention, indicating the time, temperature, materials and concentrationof chemicals involved in each step according to the preferred procedure.

500 pounds of knit Jersey cloth is placed in mesh bags, 12 pounds of theknit Jersey cloth in each bag. A scouring bath is made up in a paddlewheel dyeing machine, having a bath ratio of 30 to 1 and containing 3%of sodium palmitate soap in water on the weight of the goods. This samebath ratio is used in all of the wet treatments referred to below. Thegoods in the bags is placed in the scouring bath and the machine is runfor thirty minutes. 'The temperature of the scouring bath is 160 F. Thebath is dropped. Two successive water rinses are made up at 160 F. andeach is run for about ten minutes and then dropped.

A water bath of dye is then made up containing on the weight of thegoods of Solontine Yellow RL (Color Index No. Direct Yellow 50) and thisbath is run in the machine with the bags of goods at boiling temperaturefor two hours.

The dye bath is then dropped and a water finishing bath is made upcontaining 2% on the weight of the goods of stearyl amide at atemperature of 100 F. The machine is run with this bath in contact withthe bags of goods for 15 minutes and then the bath is dropped.

The bags of goods are then transferred to a centrifuge and thenextracted for about ten minutes.

The bags are then opened and the loose goods, immediately thereafter, inthe sense that the goods are brought through the process from thescouring bath, are not yet fully dry, are placed in a tumble drum androtated at approximately 8 r.p.m. for about 40 minutes. An extremelysoft, relaxed product is obtained, with possibility of future shrinkageso far removed that the finished garments would never have over 1%shrinkage. As pointed out hereinbefore another effect of the tumbling isto dry the goods.

When reference is made herein to knitted goods, it is intended todesignate knitted goods of the type used for underwear and for jacketssuch as cotton Jersey cloth, and is not intended to include hosiery.

In view of our invention and disclosure variations and modifications tomeet individual whim or particular need will doubtless become evident toothers skilled in the art, to obtain all or part of the benefits of ourinvention without copying the structure and process shown, and we,therefore, claim all such insofar as they fall within the reasonablespirit and scope of our claims.

Having thus described our invention what we claim as new and desire tosecure by Letters Patent is:

1. The process of dyeing, preshrinking and finishing [garments of]cotton [Jersey] jersey cloth for use in garments, which comprisesplacing the [garments of] cotton [Jersey] jersey cloth in bags, makingup a scouring bath in a paddle wheel dyeing machine, placing the bags ofthe [garments of] cotton [Jersey] jersey cloth in said paddle wheeldyeing machine, agitating the scouring bath and the [garments of] cotton[Jersey] jersey cloth in the bags by running the paddle wheel while thebags of [garments of] cotton [Jersey] jersey cloth are in the scouringbath and thereby scouring the [garments of] cotton [Jersey] jerseycloth, dropping the scouring bath, rinsing the [garments of] cotton[Jersey] jersey cloth in the paddle wheel dyeing machine, making up adye bath in the paddle wheel dyeing machine and agitating the [garmentsof] cotton [Jersey] jersey cloth by running the paddle wheel while thebags of [garments of] cotton [Jersey] jersey cloth are free in said dyebath, dropping said dye [baths] bath, rinsing the [garments of] cotton[Jersey] jersey cloth, making up a finishing bath in said paddle wheeldyeing machine containing a cationic finish, agitating said [garmentsof] cotton [Jersey] jersey cloth by running said paddle wheel while the[garments of] cotton [Jersey] jersey cloth [are] is in said finishingbath, extracting the moisture from said [garments of] cotton [Jersey]jersey cloth, removing the [garments of] cotton [Jersey] jersey clothfrom said bags, and immediately thereafter tumbling the [garments of]cotton [Jersey] jersey cloth free from the bags until [they are] saidcloth is dry.

2. The process of claim 1, in which said finishing bath essentiallycomprises an amide of a long chain fatty acid having from 14 to 30carbon atoms in the carbon chain.

Unwin: J. Soc. Dyers and Col., 1948, pp. 245-258.

Marsh: An Introduction to Textile Finishing, 1948, pp. 240-256, 270-273,published by Chapman and Hall Ltd., London, England.

Technical Manual and Year Book of the American Association of TextileChemists and Colorist, 1957, vol. 33,

